1. Field of the Invention
The present invention relates to exposure control and display control of an image capture apparatus.
2. Description of the Related Art
Conventionally, some image capture apparatuses have a function of allowing the user to compensate the exposure level; that is, a so-called exposure compensation function. Some of these image capture apparatuses allow the user to set an exposure compensation value while checking the effect of exposure compensation by displaying an image reflecting exposure compensation on a display unit. However, when photometry is performed while an exposure compensation value set by the user is reflected on the exposure level, the exposure level deviates from an optimum exposure level, decreasing the photometric accuracy. Especially when the exposure compensation value is set in the positive direction (the direction in which brightness increases) and reflected on the exposure level, an image data signal is saturated, disabling normal photometry processing.
To solve this problem, some conventional image capture apparatuses display, on a display unit, an image reflecting an exposure compensation value while maintaining the photometric accuracy. For this purpose, the gain of an amplification means for an output from the image sensor is compensated by the exposure compensation value, while the exposure time of an image sensor is controlled based on the illuminance of an object. This technique is described in, for example, Japanese Patent Laid-Open No. 2003-163833.
However, the technique described in Japanese Patent Laid-Open No. 2003-163833 implements compensation of the exposure level by only signal amplification without using the stop or exposure time. In particular, when the exposure compensation value is large, the noise of a display image increases.